The purpose of this study was to investigate the long-term training effect of wearable hip-assist robot on locomotion function in elderly adults.

Seven elderly participants (age means: 74.5±5.78, 3 males) were recruited. The Gait Enhancing Mechatronics System (GEMS, Samsung Electronic Co., Ltd., Korea), which functions as a wearable hip-assist robot was used. All participants received 45-minute gait training with GEMS in various overground environments for 24-sessions during the consecutive 8 weeks. Muscle efforts were acquired and analyzed using the 12-channel surface electromyography system (Desktop DTS system, Noraxon, USA) at preferred speed. Gait functions were determined by 3D motion capture system (Motion Analysis Corporation, USA). Cardiopulmonary metabolic energy consumption measurements were obtained during 6minutes of treadmill walking using portable cardiopulmonary metabolic system (COSMED K4B², Rome, IT). In addition, cerebral oxygenation was measured using the fNIRS imaging system (NIRSport, NIRx Medical Technologies LLC, Glen Head, NY, USA).

The 24-sessions of long-term intensive locomotion training with GEMS significantly improved gait function of elderly adults (P<0.05). Metabolic energy consumption during 6minutes treadmill walking was significantly lower after 24-sessions training (P<0.05). Furthermore, long-term intensive locomotion training with GEMS demonstrated decreased activity of specific brain regions related with gait and might represent increased efficiency of neural resources. These gains were maintained for 4 weeks after the cessation of training (P<0.05).

The results of this preliminary study suggest that long-term intensive locomotion rehabilitation with the GEMS were tolerable and effective for improving gait function, cardiopulmonary metabolic efficiency and cerebral oxygenation patterns during walking in the elderly. Randomized controlled trial with larger participants is invited in near future.